In an attempt to optimize the energy used by vehicles, as well as improve vehicle performance, many factors relating to the air flowing around vehicles are considered. Particularly, to reduce the effect of aerodynamic drag, many vehicles are given streamlined, aerodynamic shapes. Such shapes allow the vehicle to slice through the air, thereby reducing the effect of drag on the vehicle. However, due to limitations presented by other facets of automotive design, automobile exteriors can only be streamlined to a certain extent. Thus, even the most streamlined, aerodynamic vehicles experience aerodynamic drag. Further, while a streamlined shape works well with high-performance sports vehicles or ultra-fuel efficient competition vehicles, other types of vehicles are not amenable to such a design. Particularly, certain sedans maintain a blunt front end for design reasons, while many trucks and SUVs maintain the blunt front ends out of both necessity and for stylistic reasons.
Vehicles having blunt front ends experience a higher level of drag, thereby deteriorating vehicle performance and efficiency. One such cause of drag is shown in FIGS. 1A and 1B. A vehicle 10 is shown driving in a forward direction. The vehicle 10 has a front end 12 holding the headlights 14, the vehicle grille 16, a front bumper 18, and a front fascia 20. The front fascia 20 is disposed immediately below the front bumper 18.
As the vehicle 10 travels in the forward direction, the front end 12 pushes through the air, creating an air flow field around the vehicle (shown by dotted lines and arrows). Vehicles with streamlined shapes tend to cut through the air more smoothly, thereby creating a less disruptive air flow field. However, the blunt front end 12 of the vehicle 10 severely deflects the air flowing around the vehicle 10.
As a result of the severe deflection of the air flow by the vehicle front end 12, the air flowing underneath the vehicle 10 impinges on the ground. FIG. 1B shows an expanded view of the vehicle front end 12, and shows in detail the cause of the impingement of the air flow on the ground. As the air flow runs into the front end 12, the air flows along the surface of the front end 12, down to the front fascia 20. As the front fascia 20 ends, the air separates from the surface and continues to flow tangentially to the surface of the front fascia 20, directly into the ground. Therefore, the bulk of the air flow is directed immediately into the ground.
After the air flow impinges on the ground, the bulk of the air flows along the surface of the ground, creating localized regions of increased pressure. The localized regions of increased pressure are shown in FIGS. 1A and 1B by the air flow lines being substantially clumped together along the ground. The increased pressure regions, in turn, result in a higher pressure on the vehicle, which, in turn, causes additional drag forces acting on the vehicle. The additional drag forces, as stated above, negatively impact the performance and efficiency of the vehicle 10.
Therefore, there is a need in the field for a vehicle front end that manipulates the air flow that passes underneath the vehicle so as to reduce the drag effect caused indirectly by the air flow impinging on the ground.